ITALIAN PROSECUTOR CALLS AGCA INCREDIBLE

By JOHN TAGLIABUE, Special to the New York Times

Published: June 26, 1985

ROME, June 25—
Mehmet Ali Agca, again contradicting previous testimony, today gave new versions of events leading to the attempted assassination of Pope John Paul II that he says was commissioned by Bulgaria.

His jumbled account during cross-examination, prompted Antonio Marini, the prosecutor, to voice doubts that the testimony could be believed.

''If he wanted to destroy his own credibility,'' Mr. Marini said, ''he has succeeded magnificently.''

Mr. Agca, looking tired and despondent at day's end, said:

''I have finished all my answers, I confirm everything. From today on I can answer no more questions. I cannot invent anything more. I have said everything.''

The chief judge, Severino Santiapichi, adjourned the proceedings until Thursday.

Day's Testimony Is Incoherent

Since the trial began four weeks ago, Mr. Agca has often reversed himself without explanation. But his testimony today was so lacking in coherence that it angered the Judge Santiapichi, prompting him to accuse the Turk of inventing answers he seemed to perceive as pleasing his interrogators.

At one point, the judge alluded to changes Mr. Agca made in pretrial testimony about a purported Bulgarian plot to murder Lech Walesa, the Solidarity founder, during a 1981 visit to Rome.

''Other colleagues interrogated you,'' the judge said, ''and you said, 'I gave that answer because I wanted to do you a favor.' Get this through your head, don't do us any favors, try to tell the truth.''

''I think somebody coached Agca,'' Mr. Consolo said, ''I think the court will find out, and those people will pay.''

Two other Bulgarians now in Sofia are being tried in absentia.

Changes About a Passport Photo

Mr. Agca also reversed his testimony about a photograph in a forged passport he used to enter Bulgaria in 1980. First he said the photo was that of another person resembling him; then he said it was his own picture, but had been retouched.

At another point, Mr. Agca said he had traveled to Rome with two fellow Turks, Oral Celik and Omer Ay, shortly before the assassination attempt, in a Ford Granada car rented from Hertz or the Europcar rental agency. Previously he had identified the mode of transportation variously as a train, a plane and a BMW car.

He also changed details of a dinner he attended with other Turks in Milan on May 9, 1981, when he was given the gun he used four days later to shoot the Pope. In earlier testimony, Mr. Agca said he had met with two Turks; today he said five Turks had been at the dinner.

Much of Mr. Agca's account evoked evident disbelief among the court, which consists of two judges and six jurors. Mr. Agca said he and his fellow Turks had left four guns and two stun grenades in their car while they dined.

''We had mutual confidence,'' Mr. Agca said, by way of explanation.

''Confidence in whom, Italian thieves?'' Judge Santiapichi countered.

In what was perhaps Mr. Agca's widest departure from previous testimony, he said the main getaway plan to be used after the shooting called for him and two Turkish associates in St. Peter's Square to drive the rented Ford to a rented house in Vienna.

Another plan, supposedly involving Bulgarians, that Mr. Agha had previously described as the basic plan was today characterized as an ''alternative solution.''

In pretrial testimony, Mr. Agca made no mention of a third Turk in the shooting or of a Ford getaway car.

Here again, his testimony seemed laden with unlikely detail. Mr. Agca said the Ford had been parked near the Egyptian Embassy, not far from St. Peter's Square. All three Turks, he said, were capable of driving the car.

Asked by Judge Santiapichi who kept the keys, Mr. Agca first hesitated, then said, ''They were in the car.''

Judge Santiapichi, with evident disbelief, asked, ''They were in the ignition, and the car was open?''